Phosphoric acid derivatives reactions

Catalysts for Transacylation Reactions of Carboxylic and Phosphoric Acid Derivatives... 

Poly(methyl 3-(l-oxypyridinyl)siloxane) was synthesized and shown to have catalytic activity in transacylation reactions of carboxylic and phosphoric acid derivatives. 3-(Methyldichlorosilyl)pyridine (1) was made by metallation of 3-bromopyridine with n-BuLi followed by reaction with excess MeSiCl3. 1 was hydrolyzed in aqueous ammonia to give hydroxyl terminated poly(methyl 3-pyridinylsiloxane) (2) which was end-blocked to polymer 3 with (Me3Si)2NH and Me3SiCl. Polymer 3 was N-oxidized with m-ClC6H4C03H to give 4. Species 1-4 were characterized by IR and H NMR spectra. MS of 1 and thermal analysis (DSC and TGA) of 2-4 are discussed. 3-(Trimethylsilyl)-pyridine 1-oxide (6), l,3-dimethyl-l,3-bis-3-(l-oxypyridinyl) disiloxane (7) and 4 were effective catalysts for conversion of benzoyl chloride to benzoic anhydride in CH2Cl2/aqueous NaHCC>3 suspensions and for hydrolysis of diphenyl phosphorochloridate in aqueous NaHCC>3. The latter had a ti/2 of less than 10 min at 23°C. 

Catalysis in Transacylation Reactions. The principal objective of the study was to evaluate 4 as an effective organic soluble lipophilic catalyst for transacylation reactions of carboxylic and phosphoric acid derivatives in aqueous and two-phase aqueous-organic solvent media. Indeed 4 catalyzes the conversion of benzoyl chloride to benzoic anhydride in well-stirred suspensions of CH2CI2 and 1.0 M aqueous NaHCC>3 (Equations 1-3). The results are summarized in Table 1 where yields of isolated acid, anhydride and recovered acid chloride are reported. The reaction is believed to involve formation of the poly(benzoyloxypyridinium) ion intermediate (5) in the organic phase (Equation 1) and 5 then quickly reacts with bicarbonate ion and/or hydroxide ion at the interphase to form benzoate ion (Equation 2 and 3). Apparently most of the benzoate ion is trapped by additional 5 in the organic layer or at the interphase to produce benzoic anhydride (Equation 4), an example of normal phase-... 

Reaction of Polychloronitrosoethanes with Phosphorous Acid Derivatives." Seriya... 

Synthesis of glycosyl phosphates by reaction of hemiacetals with activated phosphoric acid derivatives... 

Most reactions of sulfuric and phosphoric acid derivatives can be rationalized by considering that the S=0 and P=0 functionalities are equivalent to the carbonyl group, and that polarization in these groups allows similar nucleophilic reactions to occur. Initial nucleophilic addition will then be followed by loss of an appropriate leaving group and regeneration of the S=0 or P=0. 

Most notably, the Antilla laboratory has employed VANOL and VAPOL phosphoric acid derivatives in several novel asymmetric transformations. In addition, TADDOL and phosphordiamide phosphoric acid derivatives have been applied in several Mannich-type reactions. 

Since A,A -disubstituted hydrazines are readily available from a variety of sources (see Volume I, Chapter 14), their dehydrogenation constitutes a widely applicable route to both aliphatic and aromatic azo compounds. Such oxidative procedures are of particular value in the aliphatic series because so many of the procedures applicable to aromatic compounds, such as the coupling with diazonium salts, have no counterpart. The oxidation reactions permit the formation not only of azoalkanes, but also of a host of azo compounds containing other functional groups, e.g., a-carbonyl azo compounds [83], a-nitrile azo compounds [84], azo derivatives of phosphoric acid [85], phenyl-phosphoric acid derivatives [86],... 

Those reactions of carboxylic acid and phosphoric acid derivatives which are susceptible to metal ion catalysis in nonenzymatic systems are almost without exception catalyzed by enzymes containing metal ions. This circumstantial evidence indicates strongly that the metal ions in the enzymatic reactions are concerned with the catalytic action, and not simply binding. 

Some phosphoric acid derivatives of 2-desoxy-D-ribose have been obtained by enzymic methods of preparation. A reaction analogous to the phosphorolysis of glycogen to D-glucose 1-phosphate241 has been effected with either hypoxanthine- or guanine-D-riboside, both of which could be split by enzymic phosphorolysis with the formation of D-ribose 1-phosphate.242 The successful conclusion of these experiments prompted similar investigations with desoxyribonucleosides. 

The reactions of the betaines I demonstrate the great variety of applications of these compounds for the preparation of substituted phosphoric and thio-phosphoric acid derivatives, and they open new routes for the synthesis of new or difficult to prepare compounds. 

The major use of phosphate is to supply phosphorous, one of the three essential plant foods, nitrogen, phosphorus, and potassium. Phosphate rock extraction from its ore, and its subsequent conversion into fertilizer materials and industrial chemicals, is a relatively mature art. Single superphosphate, a mixture of monocalcium monohydrate and gypsum formed by the reaction of sulfuric acid with phosphate rock, has been used as a fertilizer since the mid-1800s. Phosphoric acid, derived by the treatment of phosphate rock with sulfuric acid so as to produce gypsum in a separable form, was manufactured in many locations by batch and countercurrent decantation methods in the 1920s. 

In iminium catalysis, both we and the group of MacMillan had observed a strong counteranion effect on the yield and enantioselectivity of the reactions. Inspired by recent use of chiral phosphoric acid derivatives... 

Tatsui G (1928) Synthesis of carboline derivatives. J Pharm Soc Jpn 48 453 159 Taylor MS, Jacobsen EN (2004) Highly enantioselective catalytic acyl-pictet-spengler reactions. J Am Chem Soc 126 10558-10559 Terada M, Uraguchi D, Sorimachi K, Shimizu H (2005) Process for production of optically active amines by stereoselective nucleophilic addition reaction of imines with C nucleophiles using chiral phosphoric acid derivative. PCT Int Appl WO 2005070875 2005-08-04... 

The reaction of the aminophosphanes t-Bu2PNH2 and F2PNH2 results in the formation of hexafluoroacetoneimine and phosphoric acid derivatives with and without addition of HFA. With aminodifluorophosphane, the expected formation of a 1,3,2-dioxaphospholane (see Section III,A,4) has been observed (263). 

Substrates usefully employed in Mannich reactions are, in general, XH compounds having nucleophilic properties, with X being equal to C, N, or other heteroatoms (Fig. 4). In particular, CH compounds are suitably activated saturated and unsaturated derivatives, and NH substrates may be amines, amides, hetcrocyclcs, etc. Out of OH sub-stratcs, alcohols are mainly able to give stable Mannich products. Sulfur- and phosphorus-containing substrates are XH derivatives having the H atom bonded to the hetcroatom in the lower oxidation state, i.e., thiols, sulfinic acids, and, respectively, phosphine and phosphorous acid derivatives. As and Se compounds have also been successfully used. All these substrates are listed in more detail in Sec. D of this chapter. 

Phosphoric acid derivatives can be conveniently discussed with the carboxylic acid derivatives, owing to their similar reaction mechanisms. The structural class is extremely important biologically, but few pharmaceutical examples within it exist. For discussions of hydrolytic reactions of the phosphoric acid derivatives, the reader is referred to the first edition of this encyclopedia. ... 

Reactions of Phosphoric Acid Derivatives.— Interest in HMPT both as a solvent and as a reactant continues. In this solvent / -unsaturated carboxylic acids are reduced by lithium to mixtures of the saturated analogues and synunetrically substituted adipic acids addition of lithium acetate gives reasonable yields of substituted glutaric acids, probably by initial metallation by lithium diethylamide (Scheme 2). Butyl-lithium, however, cleaves... 

The two terminal linkages of the triphosphate are phosphoric acid anhydrides i.e. they are activated phosphoric acid derivatives and nucleophilic attack at the electrophilic y OT P phosphorus is thermodynamically very favourable. The advantage of phosphoric anhydride derivatives over acyl derivatives is that the former are kineti-cally stable in neutral aqueous solution unless a suitable enzyme is present to catalyse its reactions. 

---